WASHINGTON 
Democrats expanded their majority in the House with historic gains by dominating the Northeast and ousting Republicans in every region.

Their defeat of 22-year veteran Rep. Chris Shays in Connecticut gave Democrats every House seat from New England. Their victory in an open seat on New York's Staten Island gave them control of all of New York City's delegation in Washington for the first time in 35 years.

Democrats also rode the coattails of a decisive victory by Barack Obama in New Mexico to win one House seat they haven't controlled in four decades and another the GOP had held for 28 years. Both were left up-for-grabs by GOP retirements.

"The American people have called for a new direction. They have called for change in America," said House Speaker Nancy Pelosi, D-Calif. Exit polls showed voters troubled by the battered economy and deeply dissatisfied with President Bush.

Democrats unseated 12 Republican incumbents and captured nine open GOP seats, capitalizing on the unusually high 29 Republican departures. Republicans were only able to knock off four Democratic incumbents.

With fewer than a dozen races undecided, Democrats had won 251 and were leading for another five. Republicans had won 171 and were leading in six. If those trends held, Democrats could have a net gain of 20 seats. And Republicans were on track for their smallest numbers since 1994, the year a Republican Revolution retook the House for the first time in 40 years.

The Democratic edge in the current Congress is 235-199 with one vacancy in a formerly Democratic seat. Two Louisiana seats, one Democratic and one Republican, won't be decided until December because hurricanes postponed their primaries until Tuesday.

It was the first time in more than 75 years that Democrats were on track for big House gains in back-to-back elections. They picked up 30 seats in 2006.

"This will be a wave upon a wave," Pelosi said.

Republicans were licking their wounds and cheered themselves mostly by the prospect that Democrats _ now holding the White House and bigger House and Senate margins _ might overreach and position the GOP for gains in 2010.

"We sort of got through this, we think, a little bit better than some people might have expected," said Rep. Tom Cole of Oklahoma, the head of the Republican House campaign committee. "Our worst days are behind us."

Still, in the first hint of what promises to be a GOP shakeup, Rep. Adam Putnam of Florida, the No. 3 Republican, told colleagues in a letter released near midnight that he was "reluctantly" stepping down from his post.

In the northeast, GOP Reps. John R. "Randy" Kuhl of New York and Phil English of Pennsylvania were defeated. Democrat Eric Massa unseated Kuhl in New York's southern tier, and Kathy Dahlkemper, a 50-year-old mother of five, toppled English in a swing district of rural communities and old industrial steel towns in Pennsylvania's northwest corner.